Patients only will also be given an injection of botulinum toxin. These injections are effective, in varying degrees, in about 60 percent of patients with abductor spasmodic dysphonia. This study will use a different approach to botulinum toxin injections to test their effect in patients with pressures higher than normal. Rather than inject the posterior cricoarytenoid muscle or the cricothyroid muscle, as is typically done, the thyroarytenoid muscle, which closes the voice box, will be injected on one side. A second one-sided injection may be given after 2 or 3 weeks if no effect is seen after the first injection. Speech will be recorded at each visit to measure any change in symptoms after the injection.